Closure for flexible container

ABSTRACT

A fastening device for securing the mating edges of a sheet of plastic material together to form a sealed container. The structure or device is constituted of three parts, two of which are secured to the respective edges of the material as strips, and take the form of &#39;&#39;&#39;&#39;C&#39;&#39;&#39;&#39; shaped elements of different sizes which can be fitted snugly one within the other. These members have flat extensions to which the edges of the plastic sheets are secured. The third member is constituted of a rod of rubber or similar stretchable material which when stretched longitudinally will temporarily reduce its diameter so that it can be pressed into the circular opening formed within the inner &#39;&#39;&#39;&#39;C&#39;&#39;&#39;&#39; shaped member. When the stretching force is removed, the rod will increase its diameter to press the inner member against the outer member and provide a sealed joint between the two members and the mating edges of the material to which they are attached.

United States Patent Robbins et al.

[451 Oct. 24, 1972 [54} CLOSURE FOR FLEXIBLE Ohio 45402; Clifford Ralph Bullock, 522 Cheshire Avenue, Fort Walton Beach, Fla. 32548 [22] Filed: Jan. 20, 1971 [21] Appl. No.2 107,919

' Related US. Application Data [63] Continuation-impart of Ser. No. 842,181, July 16, 1969, abandoned.

[52] US. Cl. ..150/3, 24/243 K, 150/6, 150/52 R, 229/62 [51] Int. Cl. ..B65d 33/16 [58] Field of Search.....229/62, 65; 150/3, 5, 6, 52 H, 150/52 K, 52 R; 24/243 K, 243 M, 243 N, 30.5 R, 201 C, 255 BC 90,167 12/1960 Denmark 2 2 9/62 1,227,837 3/1960 France ..24/243K 1,341,025 9/1963 France ..150/3 Primary Examiner-Donald F. Norton Attorney-Harry A. Herbert, Jr. and Richard J. Killoren [57] ABSTRACT A fastening device for securing the mating edges of a sheet of plastic material together to form a sealed container. The structure or device is constituted of three parts, two of which are secured to the respective edges of the material as strips, and take the form of C shaped elements of different sizes which can be fitted snugly one within the other. These members have flat extensions to which the edges of the plastic sheets are secured. The third member is constituted of a rod of rubber or similar stretchable material which when stretched longitudinally will temporarily reduce its diameter so that it can be pressed into the circular opening formed within the inner C shaped member. When the stretching force is removed, the rod will increase its diameter to press the inner member against the outer member and provide a sealed joint between the two members and the mating edges of the material to which they are attached.

8 Claims, 8 Drawing Figures PATENTEDIIBT24 m2 I 3.700.019

SHEET 2 [IF 2 CLOSURE FOR FLEXIBLE CONTAINER CROSS-REFERENCE TO RELATED APPLICATIONS This is a continuation-in-part of our patent application CLOSURE FOR FLEXIBLE CONTAINER Ser. No. 842,181, filed July 16, 1969 and now abandoned.

BACKGROUND OF THE INVENTION In the art of fastening the edges of a bag or covering together so as to protect the product inside from weather, dampness, etc., it has been customary to employ the zipper form of closure. However, when the bag or container serves as a covering for a large product such as an airplane engine, a missile or projectile, the zipper fastener becomes expensive on account of the length of the opening in the bag which has to be closed. Moreover, the slide of the zipper is relied upon, not only to pull the mating edges together but also to hold them in a seal-tight relation. Consequently, any wear at the teeth of the zipper, particularly if the latter were constituted of plastic material for economy reasons, tends to weaken this holding effect and allow slight but important leakage at the joint. Other forms of running or strip seals, on account of the length of the opening to be closed, generally require special and complicated tools for bringing the edges of the opening together and holding them while the seal is being formed. The same, or a similarly expensive tool, is also required to loosen the grip of the teeth in order to unfasten the sealed members.

SUMMARY OF THE INVENTION According to this invention a relatively rigid C shaped element is sealed to one side of the opening in the container with a smaller diameter flexible C" shaped element sealed to the other side of the opening in the container. The smaller C shaped element is adapted to fit within the larger C shaped element. A rod of rubber or other stretchable material is secured at one end of the opening and when stretched to reduce its diameter can be pressed into the C shaped members to provide a sealed joint between the members.

An object of the invention is to provide a fastening device of inexpensive but effective character for closing and sealing the opening in a bag or covering which contains objects of any shape, size or length.

Another object is to provide a flexible container made of plastic material, suitable for encompassing large military equipment and in'providing an improved sealed closure for the necessary large opening which has to receive the equipment.

Still another object is to provide a closure device for sealing the opening in large and small containers, and in which no part is necessarily constituted of metal, and the gripping teeth formed, for example in a zipper, are completely avoided.

A further object is to provide a water vapor/gaseous tight seal for a flexible container which is easy to operate without special tools, either in forming the seal or disengaging the seal, to remove the contained product. The parts are economical to manufacture in that they lend themselves to quantity production, and are readily installed along the edges of the opening to be sealed. Other objects and features will be apparent when the following specification is perused in connection with the accompanying drawings.

DETAILED DESCRIPTION OF DRAWINGS FIG. 1 represents an end view of the so-called inner clamping member which forms part of the sealed structure.

FIG. 2 is a fragmentary plan view of the member shown in FIG. 1.

FIG. 3 depicts an end view of the outer clamping member.

FIG. 4 is a fragmentary plan view of the outer member.

FIG. 5 shows a short portion of an extensible rod for pressing the two clamping members together.

FIG. 6 shows, in perspective, the manner of inserting the rod in order to clamp both the inner and outer clamping members together.

FIG. 7 illustrates, in perspective, a modified form of the fastening device and in which the inner clamping member is omitted.

FIG. 8 illustrates, in perspective the fastening device of FIG. 6 with the securing means for the free end of the clamping rod.

In FIG. 1, reference character 1 designates a C shaped portion or element and there is a pair of outwardly extending wing portions 2 integrally connected with the portion 1. The wing elements 2 extend from a necked-down portion of the upper C" shaped member 1, and are of sufficient width as to offer a firm contact with one of the edges of the opening in the container (not shown in FIG. 1). The structure referred to in FIG. 1 will be designated hereinafter as the inner clamping device.

In FIG. 3, there is shown the outer clamping device at 3 and as in the case of the inner portion, the structure 3 is provided with two outwardly extending wings 4 integrally attached at the necked-down portion of the member 3. The latter, as in the case of the portion 1 in FIG. 1, also takes on an inverted C shape and the interior diameter designated at 5 is approximately the same as the outer diameter of the portion 1 so that the inner clamp member can be fitted snugly within the circular recess of the structure shown in FIG.

3. It-will be noted that the latter is of greater thickness throughout, including the wings 4, than the thickness of the clamping member 1 and its wings 2.

Thus, the outer clamping member will be more rigid than the inner clamping member when they are made of the same material. The inner clamping member must be made more flexible so that it can be fitted into the outer clamping member. The outer and inner members could also be made of different materials. For example the material of the outer member could be made of simi-rigid polyethylene and the material of the inner member could be made of flexible ethyl vinyl acetate.

The outer member must be more rigid to maintain the sealing relation between the members and since there is somewhat greater strain that is placed on the outer clamping member 3, when pressure is brought against its inner surface by the outer surface of the clamping member 1, as will be described hereinafter.

However, the overall width of the wings 4 is approximately the same as the width of the wings 2. The length of outer clamping member 1, may be slightly greater than the length of the opening in the container or bag 6 to be closed, and the length of the opening depends on the length of the product which is to be contained within the bag or container. The container and its improved fastener can advantageously be used as a covering for military equipment of extreme length such as missiles, projectiles, and may also take on a large circumferential size to accommodate engines for aircraft being transported by plane to foreign countries, where lightness in weight is a prime consideration. The bags or covering can be made of plastic material, of any suitable and well-known type, and should be of sufficient thickness to be rugged and withstand any tearing effect. It is most desirable that the plastic material of the bag should be flexible so as to lend itself to the many contours of the contained product or products. The inner and outer clamp members 1, 3, can also advantageously be made of plastic material and can be readily extruded to exact shape and dimension by presses, even of the great lengths of the bag or container as will accommodate the longest missile or projectile.

In operation, the first step is to apply a water-proof plastic cement of any suitable and well-known kind to the under side of the left hand wing member 2, as seen in FIG. 6. The edge of the bag to the left of the opening 7 is then pressed against the under surface of this wing portion 2. The edge surface of the bag extends across this wing portion as far as possible toward the neck of the C shaped member. The next step is to press the inner clamp member into the outer clamp member 3, and as stated hereinbefore, this is a snug fit. The wing portions 2 and 4 of the respective clamp members will abut one another as seen in FIG. 6. The portion of the bag or container to the right of the opening 7 is then secured by the water-proof plastic cement to the under side of the right hand wing portion 4, the edge of the bag extending inwardly as far as possible so as to obtain the maximum holding effect. Ordinary and well-known tools such as a roller can be employed to advantage in pressing the bag portion at the left of the opening against the under side of the wing 2, and also to press the opposite edge portion of the bag against the under side of the wing portion 4.

In order to effect a seal between the inner and the outer clamping members, we employ a rod 8 of ordinary rubber but which may be constituted of sponge rubber and having a length slightly greater than the length of the clamping members. The diameter of this rod is slightly greater than the interior diameter of the inverted C" shaped element 1. The rod 8 is secured to bag 6 at the end as shown at 11. The outer clamping member 3 may extend beyond the end of the opening in bag 6 and the rod 8 may be secured in the end of the outer member 3. When one end of the rod is held firmly by hand and a pull is exerted on the rod so that it stretches, the diameter of the latter becomes smaller and can readily be wedged or pressed downwardly, for example by means of an ordinary metal bar, past the necked-down portion of the inner clamp member 1 where it will seat within that member as shown in FIG. 6. Upon release of the pull on the rod, the latter will foreshorten and its diameter will tend to increase considerably. The pressure produced by this increase is sufficient to force the inner clamp member 1 against the interior surface of the outer clamp member 3, and thus provide a circumferential seal between these two members. A tremendous force can be exerted by the rod outwardly in this manner so that an effective seal is produced over the entire lengths of the contiguous surfaces of the two inverted C" shaped portions of the clamps.

In order to release the seal, it is merely necessary to pull again on the rod 8 by releasing end portion 12 from retainer 13, as shown in FIG. 8 and again stretching the rod to pull it past the necked-down portion of the inner clamp member in view of the decreased diameter assumed by the rod. The opposite edges of the bag or enclosure 6 are then released from one another by merely disengaging the circular portions of the clamp elements 1, 3 since the bag portion to the left of the opening is cemented only to the inner side of the left hand wing portion 2, whereas the portion of the bag to the right of the opening is secured to the under side of the right hand wing portion 4. Since the inverted 'C shaped portions 1 and 3 are physically separate from one another, the opening in the bag becomes unfastened even though the edges along the opening have secured thereto a part of each of the clamp structures. The clamping or sealing devices can be used over again to seal the edges of the bag by simply reversing this process namely by pressing the clamping devices together, assuming the bag portions are still attached and apply the rubber rod in an elongated stretched condition. Since the securement between the edges of the bag at the opening, and the flat wings of the clamp members are air and water tight, and further due to the strong sealing surface effected around the partial circumference of the Cshaped portions, the edges of the bag are completely sealed from the slightest trace of water vapor, water or gas so that the contents of the bags sealed in this manner will arrive at their destination in precisely the same condition as when placed within the protection of the bag.

FIG. 7 shows a modified form of the clamping structure. In this case, a portion of the bag material is used to form the inner clamping member 1 and the sealing function is performed by the member 3 together with the portion of the bag material and the rubber rod. In this figure, an area of the bag 6 to the right of the opening is secured as before by a suitable plastic cement to the under side of the right hand wing member 4. However, the bag area at the left of the opening is not secured to the clamping device but instead passes freely over the upper surface of the left hand wing member 4. The material is temporarily pressed down into the circular recess of the clamp member 3, and excess length, as indicated at 9, extends beyond the recess. The rubber rod 8 is applies as before by axial pull assuming one end of the rod is firmly held and when the diameter has decreased, the rod is pressed down into the circular recess where it contacts the circular portion of the bag. In this case, the rubber rod, upon being released from the longitudinal pull, serves to press the bag material against the circular recess of the clamp structure 3 and in this manner an effective seal between the bag portion to the left of the opening and the clamp member 3 is efiected. It is apparent, in this case, that the diameter of the rod 8 of necessity is slightly smaller than the rod referred to in FIG. 6 for the reason that there is an intervening thickness of the bag material between the rod and the inside surface of the C shaped portion 3. As in the case of structure shown in FIG. 6, the bag can be opened in order to remove the contained products by again pulling on the rod 8 in order to decrease its diameter, at which time it can be readily pulled out of the circular recess. Since the bag material to the left of the opening is not secured to the left hand wing portion 4, there is no hindrance to separating the edge areas of the bag in the region of the opening.

We claim:

1. A closure for a container having an elongated opening with edges which are adapted to be closed, comprising: at least one closure sealing member having a C shaped portion; the container material at one edge of the opening being secured to said closure member, a second sealing member, at the other edge of the opening, extending over the one closure member and having a portion extending into the C shaped portion and means including a round rod of material adapted to have its diameter reduced when a pulling force is asserted at the ends thereof and adapted to be inserted into the portion of said second sealing member extending into the circular recess formed by said C shaped portion and when released within the C" shaped portion pressing the second sealing member into intimate contact with the inner surface of the C shaped portion of the closure member to form a seal.

2. A closure for a container having open edges according to claim 1 in which the one closure sealing member has fiat wing portions extending outwardly from the C shaped portion with the container at one edge of the opening being secured to one of the fiat wing portions.

3. A closure for a container having open edges according to claim 2, wherein said second sealing member is formed as a portion of container material extending over the one closure member and having a portion extending into the C shaped portion of the one closure sealing member.

4. A closure for a container having open edges according to claim 2 wherein the second sealing member has an inverted C shape portion and flat wing portions extending outwardly from the C shaped portion, said C shaped portions of the sealing members being of different diametrical sizes so that the C shaped portion of the second sealing member fits snugly within the C shaped portion of the one sealing member when the wing portions are in abutting relation, the container material adjacent the other edge of the opening being secured to one of said wing portions of the second sealing member.

5. A closure for a container having open edges according to claim 4 and in which the container is constituted of flexible plastic material and the sealing members are each constituted of plastic material in strip form extending along the container portions adjacent the edges of said opening.

6. A closure for a container having open edges according to claim 4 and in which the container material adjacent one of said edges of the opening is firmly secured to the lower surface of the wing portion of the member with the C shaped portion of larger size, and

the container material at the other of said edges is secured to the lower surface of the wing portion of the member with the C shaped portion of smaller size.

7. A closure for a container having open edges according to claim 2 and in which said rod is constituted of rubber.

8. A closure for a container having open edges which are adapted to be closed and sealed together, said closure comprising a closure member having a C shaped portionwith flat wing portions extending outwardly on opposite sides of said member, the container material at one of the edges of the opening extending to the top surface of one of said wing portions and being continued to follow the interior surface of the inverted C shaped member, the container material at the other edge of the opening being secured to the bottom surface of the other of said wing portions, a circular rodlike element adapted to be elongated by force exerted along its axis in order to reduce its diametral size being pressed into the interior opening of said inverted C" shaped member against the container material which extends around the inner surface of said member whereby upon release of said force, the diameter of the rod-like element is caused to increase and thereby press said container material against the interior surface of said member to effect a seal between the open edges of the container. 

1. A closure for a container having an elongated opening with edges which are adapted to be closed, comprising: at least one closure sealing member having a ''''C'''' shaped portion; the container material at one edge of the opening being secured to said closure member, a second sealing member, at the other edge of the opening, extending over the one closure member and having a portion extending into the ''''C'''' shaped portion and meAns including a round rod of material adapted to have its diameter reduced when a pulling force is asserted at the ends thereof and adapted to be inserted into the portion of said second sealing member extending into the circular recess formed by said ''''C'''' shaped portion and when released within the ''''C'''' shaped portion pressing the second sealing member into intimate contact with the inner surface of the ''''C'''' shaped portion of the closure member to form a seal.
 2. A closure for a container having open edges according to claim 1 in which the one closure sealing member has flat wing portions extending outwardly from the ''''C'''' shaped portion with the container at one edge of the opening being secured to one of the flat wing portions.
 3. A closure for a container having open edges according to claim 2, wherein said second sealing member is formed as a portion of container material extending over the one closure member and having a portion extending into the ''''C'''' shaped portion of the one closure sealing member.
 4. A closure for a container having open edges according to claim 2 wherein the second sealing member has an inverted ''''C'''' shape portion and flat wing portions extending outwardly from the ''''C'''' shaped portion, said ''''C'''' shaped portions of the sealing members being of different diametrical sizes so that the ''''C'''' shaped portion of the second sealing member fits snugly within the ''''Cshaped portion of the one sealing member when the wing portions are in abutting relation, the container material adjacent the other edge of the opening being secured to one of said wing portions of the second sealing member.
 5. A closure for a container having open edges according to claim 4 and in which the container is constituted of flexible plastic material and the sealing members are each constituted of plastic material in strip form extending along the container portions adjacent the edges of said opening.
 6. A closure for a container having open edges according to claim 4 and in which the container material adjacent one of said edges of the opening is firmly secured to the lower surface of the wing portion of the member with the ''''C'''' shaped portion of larger size, and the container material at the other of said edges is secured to the lower surface of the wing portion of the member with the ''''C'''' shaped portion of smaller size.
 7. A closure for a container having open edges according to claim 2 and in which said rod is constituted of rubber.
 8. A closure for a container having open edges which are adapted to be closed and sealed together, said closure comprising a closure member having a ''''C'''' shaped portion with flat wing portions extending outwardly on opposite sides of said member, the container material at one of the edges of the opening extending to the top surface of one of said wing portions and being continued to follow the interior surface of the inverted ''''C'''' shaped member, the container material at the other edge of the opening being secured to the bottom surface of the other of said wing portions, a circular rod-like element adapted to be elongated by force exerted along its axis in order to reduce its diametral size being pressed into the interior opening of said inverted ''''C'''' shaped member against the container material which extends around the inner surface of said member whereby upon release of said force, the diameter of the rod-like element is caused to increase and thereby press said container material against the interior surface of said member to effect a seal between the open edges of the container. 